1. Field of the Invention This invention relates to a portable computer, more particularly to a portable computer with a detachable cartridge type interface device to permit the portable computer to achieve a wide variety of functions without increasing its size.
2. Description of the Related Art Presently, computers are in widespread use because of the conveniences they bring. Among the many types of computers available, the personal computer is generally preferred by most students and offices because of its relatively small size and affordable price. However, the personal computer is relatively heavy and cannot be conveniently carried. This led to the development of smaller portable computers which are lighter and which can be conveniently carried. Examples of existing portable computers include notebook and laptop computers. Because the size of the portable computer has been reduced, its functions are correspondingly limited. To achieve additional functions, the portable computer must be provided with an interface card connector so that the portable computer may be used with a mouse, a modem, etc. FIG. 1 is an illustration of the computer casing (A) of a conventional portable computer with detachable interface card. The computer casing (A) is substantially L-shaped and has a central processing unit (CPU) receiving space (Al) and an interface card receiving space (A2). A first socket connector means (A3) is mounted on the computer casing (A) at a rear end of the CPU receiving space (Al) and is electrically connected to the CPU (not shown). A second socket connector means (A4) is electrically connected to the first socket connector means (A3) and is provided in the interface card receiving space (A2). A lid (A5) is hinged on an open top end of the interface card receiving space (A2). Note that while the portable computer incorporating the computer casing (A) can achieve additional functions, its size is correspondingly increased because of the presence of the interface card receiving space (A2).